SPACI score report for 2z4n in ASTRAL 1.75:

PDB Entry: 2z4n
SPACI score: -0.05
AEROSPACI score: -0.05

Experiment type: XRAY
Resolution: 4.45
R-factor: 0.263
PCK1 PROCHECK Ramachandran: 3
PCK2 PROCHECK Chi-1 angle: 3
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -4.567
WCK2 WHAT_CHECK Ramachandran: -7.551
WCK3 WHAT_CHECK Chi angles: -6.006
WCK4 WHAT_CHECK Backbone: -4.736

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).